Technical Field
The present invention relates to an image lens assembly system. More particularly, the present invention relates to a compact image lens assembly system applicable to electronic products.
Description of Related Art
In recent years, with the popularity of mobile products with camera functionalities, the demand of miniaturized optical lens systems is increasing. The sensor of a conventional photographing camera is typically a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal-Oxide-Semiconductor) sensor. As the advanced semiconductor manufacturing technologies have allowed the pixel size of sensors to be reduced and compact optical lens systems have gradually evolved toward the field of higher megapixels, there is an increasing demand for compact optical lens systems featuring better image quality.
A conventional compact optical lens system employed in a portable electronic product mainly adopts a five-element lens structure such as the one disclosed in U.S. Pat. No. 8,000,031. Due to the popularity of mobile products with high-end specifications, such as smart phones and PDAs (Personal Digital Assistants), the pixel and image-quality requirements of the compact optical lens system have increased rapidly. However, the conventional five-element lens structure cannot satisfy the requirements of the compact optical lens system.
Although other conventional optical lens system with six-element lens structure is disclosed, such as U.S. Publication No. 2012/0170142. However, the two lens elements of the optical lens system closest to the object side are not configured as one with negative refractive power and the other with greater positive refractive power, so that the back focal length of optical lens system cannot be reduced. As a result, when the field of view of the optical lens system is increased, the total track length thereof is getting hard to be maintained, and the aberration and the distortion thereof cannot be eliminated by the mutual compensating effect generated from the aforementioned two lens elements.